液晶分子优化给体材料组装制备高性能有机太阳能电池  

Liquid-crystal-molecule Assisted Donor Materials Assembly for High-performance Organic Solar Cells

作　　者：曾光[1] 张奔 李耀文[1] Guang Zeng;Ben Zhang;Yao-wen Li*(Suzhou Key Laboratory of Novel Semiconductor-optoelectronics Materials and Devices,Soochow University,Suzhou 215123)

机构地区：[1]苏州大学苏州市新型半导体光电材料与器件重点实验室,苏州215123

出　　处：《高分子学报》2024年第6期698-708,共11页Acta Polymerica Sinica

基　　金：国家自然科学(基金号52325307,52273188,22075194,51820105003);国家重点研发计划项目(项目号2020YFB1506400);江苏省高等学校自然科学基金(基金号20KJA430010)资助项目

摘　　要：活性层形貌优化是实现高效、稳定的体异质结有机太阳能电池(OSC)的关键,添加剂工程被广泛用于优化OSC活性层的膜形貌.基于此,本文工作提出了一种利用具有简单结构的液晶分子4-氰基-4'-庚基联苯(7-CB)作为添加剂优化给体聚合物(PM6)在共混膜中聚集行为的策略.通过掠入射广角X射线散射、原位吸收光谱及分子动力学模拟等表征发现,7-CB通过与PM6的烷基侧链之间的范德华力和CH/π相互作用诱导PM6规整排列,增强了PM6之间的相互作用,提高了活性层薄膜的结晶度.得益于此,无任何后处理的活性层薄膜中电荷传输得到改善,电荷重组被大幅抑制.基于7-CB处理的PM6:L8-BO制备的硬质和柔性二元OSCs效率分别从15.41%和14.90%提高到18.01%和17.26%.The optimization of the active layer morphology is the key to achieving efficient and stable bulk heterojunction organic solar cells(OSCs),and additive engineering is widely used to optimize the film morphology of the active layer in OSCs.A strategy is proposed to optimize the aggregation behavior of donor polymer(PM6)in blended films by using a simple liquid crystal molecule 4-cyano-4'-heptylbiphenyl(7-CB)as an additive.Through wide-angle X-ray scattering,in situ absorption spectroscopy and molecular dynamics simulation,it was found that 7-CB induced the regular arrangement of PM6 through the van der Waals force and CH/πinteraction with the alkyl side chain of PM6,which enhanced the interaction between PM6 and PM6,and then enhanced the preaggregation of PM6 in solution,thus improving the crystallites of the active layer film.Benefit from this,charge transfer in the active layer film without any post-treatment is improved,and charge recombination is greatly suppressed.The power conversion efficiency of rigid and flexible binary OSCs prepared by PM6:L8-BO based on 7-CB treatment was increased from 15.41%and 14.90%to 18.01%and 17.26%,respectively.

关 键 词：有机太阳能电池 添加剂 自组装 

分 类 号：TM914.4[电气工程—电力电子与电力传动]